I ran into a situation again where I was wondering what the different combinations of unique/constraint in the entity editor results in.
So I made an overview matrix for future reference.
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Hello,
Nice work, thank you.
Also, what a coincidence, I was thinking about that yesterday!
Just to add that, although same in effect, unique index and unique constraint are not the same.
On most databases, unique constraint will automatically create unique index, while unique index can exist without a constraint. Constraint is meant to enforce data integrity, and is added by ALTER TABLE, while indexes are meant to speed up the retrival of data, and in this case are also enforcing integrity by not allowing duplicates.
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